Integrins in multiple myeloma.

Integrins have crucial roles in BM homing, survival, proliferation, or drug resistance of multiple myeloma (MM) cells. Especially, integrin alpha4beta1 (VLA-4) and alpha4beta7 has been reported to have important functions in MM cells, and therefore are potential therapeutic targets. We have recently shown that integrin beta7 constitutively adopts the active conformation specifically in MM cells, and found that chimeric antigen receptor (CAR) T cells targeting the activated conformation of integrin beta7 is promising for MM. Although the mechanism for the constitutive activation is still being investigated, our results indicate that integrin conformation is different between MM and normal cells and suggest that it may be associated with the pathology of MM.